Space junk at 'tipping point', now getting worse on its own

Satellites and spacecraft face the growing risk of damage and failure thanks to the expanding volume of small pieces of junk hurtling around the Earth's orbit.

Scientists have warned the amount of orbital junk has reached a tipping point in volume and size.

The National Research Council has said in a report (here) that existing debris from other satellites and space craft will only multiply as it continue to collide with itself, getting ever smaller into the bargain.

"This increase will lead to corresponding increases in spacecraft failures, which will only create more feedback into the system, increasing the debris population growth rate," the report says.

So far the problem has been largely restricted to low Earth orbit (LEO), but geosynchronous Earth orbit (GEO) could suffer the same fate over a longer period of time. GEO is the band of space 23,500 miles above the equator where an orbiting satellite remains constantly above the same point on the surface, and is home to many communications satellites.

The Council has recommended NASA develop a strategic plan for its current programmes – grouped under the banner meteoroid and orbital debris (MMOD) – to monitor and tack space debris. It urged for a prioritisation of resources and research projects to record, monitor and report on the shrinking pieces of junk.

The scientists warned NASA's current vogue for budget cuts could threaten MMOD efforts, as many of the programmes are run by a single person.

They pointed out how, in the past, MMOD work has helped redesign satellites' critical components to be more resistant to MMOD damage, and develop MMOD shielding on the International Space Station.

The crew of the ISS in June were forced to man their escape capsules and prepare for an evacuation when debris came dangerously close to the station. ®